On Fri, Mar 02, 2007 at 10:19:17AM +0100, Thomas Gleixner wrote: > On Fri, 2007-03-02 at 07:11 +0100, Willy Tarreau wrote: > > > Call Trace: > > > [<c0127d49>] posix_cpu_clock_get+0x47/0xdc > > > [<c0125bf3>] sys_clock_gettime+0x80/0x82 > > > [<c0103bfc>] syscall_call+0x7/0xb > > > [<c02f0000>] svc_ioctl+0xc2/0x261 > > > ======================= > > > Code: 0b eb fe 57 56 53 89 cb 89 d1 8b 74 24 10 83 e0 03 83 f8 02 74 0c > > > 89 f2 89 c8 5b 5e 5f e9 ee 3f ff ff bf 00 ca 9a 3b 89 d0 89 da <f7> f7 89 > > > 56 04 89 06 5b 5e 5f c3 55 57 56 53 89 c7 89 d6 89 cb > > > EIP: [<c0126a07>] sample_to_timespec+0x28/0x33 SS:ESP 0068:d4a56f74 > > > > > > The instruction is: > > > > > > div %edi > > > > > > And edi is 1e9 (0x3b9aca00). I don't understand why this results in an > > > divide error. > > > > It does this because 'div' does an unsigned divide of edx:eax by edi. > > Here, edx=fffffffa and eax is 63b5a669. Clearly, such a number cannot > > be divided by 1e9 to return a 32 bits value. > > > > Given the values we see here, I suspect the code should have used an > > integer divide (idiv). This means that something in the code implies > > that the result is unsigned while it should be signed. > > The question is why do we have this negative value in the dividend. I > suspect this is related to > > http://marc.theaimsgroup.com/?l=linux-kernel&m=117210430112543&w=2 > > Sean, can you please retest with that patch applied, which hit mainline > after 2.6.21-rc2
Yup, this fixes it. And clock_gettime(CLOCK_THREAD_CPUTIME_ID) returns nice high resolution times. :) Thanks Sean - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
